The Harford County Sheriff's Office said 20-year-old Christopher McCullough and 20-year-old Darrius Johnson got into a heated exchange in the 1400 block of Valley Forge Way around 5 a.m. Sunday.

At some point, police said they believe McCullough stabbed Johnson and ran away.

Johnson was taken to Upper Chesapeake Medical Center to be treated for a stab wound to the chest. He was then flown to Shock Trauma, where he remains in critical condition.

McCullough was arrested Sunday night after police said he tried to run from a home where officers had found him in the 600 block of Yorkshire Drive in the Harford Square community. He was charged with first-degree attempted murder and assault.